Waist-to-height ratio, body mass index and waist circumference for screening paediatric cardio-metabolic risk factors: a meta-analysis

Effect of Time-Varying Exposure to School-Based Health Promotion on Adiposity in Childhood

BACKGROUND

The results of most school-based health promotion initiatives are inconclusive.

OBJECTIVES

This trial assessed the effect of time-varying exposures to a multicomponent school-based health promotion intervention (SI! Program) on adiposity markers.

METHODS

A total of 48 schools in Madrid (Spain) were cluster randomized to receive the SI! Program through elementary education grades 1 to 6 (E1-6, 12 schools, 459 children), 1 to 3 (E1-3, 12 schools, 513 children), or 4 to 6 (E4-6, 12 schools, 419 children) or to receive the standard curriculum (control, 12 schools, 379 children). The primary endpoint was the between-group difference at 3- and 6-year follow-up in the change from baseline in adiposity markers and the overall knowledge-attitudes-habits (KAH) score.

RESULTS

At 3-year follow-up, children who had the intervention showed significantly lower increases than the control group in z-scores for body mass index (BMI), waist-to-height ratio (WHtR), and waist circumference (WC) (zBMI: -0.09; 95% CI: -0.16 to -0.03; P = 0.003; zWC and zWHtR: -0.19; 95% CI: -0.28 to -0.10; P < 0.001). At 6-year follow-up, the beneficial trend in zWC and zWHtR was maintained in the E1-6 and E1-3 groups: difference zWC control vs E1-6 (-0.19; 95% CI: -0.36 to -0.03; P = 0.020), control vs E1-3 (-0.22; 95% CI: -0.38 to -0.06; P = 0.009); difference zWHtR control vs E1-6 (-0.24; 95% CI: -0.41 to -0.06; P = 0.009), and control vs E1-3 (-0.29; 95% CI: -0.47 to -0.11; P = 0.001). No significant between-group differences were found in the change of overall KAH score.

CONCLUSIONS

Early elementary school interventions may be more effective than later interventions on abdominal adiposity. Further research should assess the sustainability effects of school-based health promotion programs.

The relationship between acrochordons, obesity, and metabolic syndrome in the pediatric population: A retrospective cohort study

BACKGROUND

Acrochordons or skin tags are common benign skin growths. Several studies explored the relationship between obesity and metabolic syndrome in adults but remains unexplored in children.

METHODS

This was a single-center retrospective cohort study of outpatient dermatology patients between 1 January 2000 to 1 January 2021. Children under 18 years old diagnosed with acrochordons using diagnostic codes International Classification of Diseases, 10th Revision (ICD-10) L91.8 and 9th Revision (ICD-9) 701.8 were included. We collected patient demographics, past medical history, laboratory values, vital signs, and physical exam. Body mass index (BMI) was calculated and stratified into categories based on the Center for Disease Control's BMI-for-Age Growth Charts. Metabolic syndrome was diagnosed when three of the five criteria were met. Data were propensity-matched and compared with NHANES (National Health and Nutrition Examination Survey), which offered a generalizable sample to the US population.

RESULTS

Fifty-five patients under 18 years old with a diagnosis of acrochordons were mostly Caucasian (76%) and female (64%). The mean BMI was 27.3, with 49.5% categorized as obese and 20% as overweight. The mean age of diagnosis was 10.1 years. Acrochordon predominantly appeared in the axilla. In our cohort, three patients (5.5%) met the criteria for metabolic syndrome. The prevalence of obesity (42% vs. 21%), type 2 diabetes mellitus (4.8% vs. 0.6%), hyperlipidemia (8.1% vs. 0%), and hypertension (1.6% vs. 0%) was greater in our cohort compared with NHANES.

CONCLUSIONS

Like the adult population, acrochordons may serve as marker for metabolic disease in the pediatric population.

Proportion and Correlates of Children in the US-Affiliated Pacific Region Meeting Sleep, Screen Time, and Physical Activity Guidelines

INTRODUCTION

Limited data on 24-hour movement behaviors of children aged 5-8 years exist globally. We describe the prevalence and sociodemographic associations of meeting physical activity (PA), sedentary recreational screen time (ST), and sleep guidelines among children from 11 jurisdictions in the US-Affiliated Pacific region.

METHODS

Cross-sectional representative data from 1192 children aged 5-8 years living in the US-Affiliated Pacific region were drawn from the baseline 2012-2014 Children's Healthy Living Program. Sleep and moderate- to vigorous-intensity PA were calculated from accelerometry. ST and sociodemographic data were collected from caregiver surveys. The percentage of children meeting the Asia-Pacific 24-hour movement guidelines for PA (≥60 min/d of moderate- to vigorous-intensity PA), sleep (≥9 and ≤ 11 h/d) and ST (≤2 h/d) were calculated. Generalized linear mixed models were used to examine associations with adiposity and sociodemographic variables.

RESULTS

Twenty-seven percent (95% confidence interval, 24.6-30.0) of children met integrated guidelines; 98% (96.2-98.0) met PA, 78% (75.4-80.0) met sleep, and 35% (32.6-38.0) met ST guidelines. Females (adjusted odds ratio = 1.40 [95% confidence interval, 1.03-1.91]) and those living in lower-middle-income jurisdictions (2.29 [1.49-3.54]) were more likely to meet ST guidelines. Overweight children (0.62 [0.40-0.96]), those aged 8 years (0.39 [0.22-0.69]), and children with caregivers of an education level of high school or beyond (0.44 [0.29-0.68]) were less likely to achieve ST guidelines. Children from midrange annual household incomes were less likely to meet combined guidelines (0.60 [0.39-0.92]).

CONCLUSIONS

Three-quarters of children are not meeting integrated Asia-Pacific 24-hour movement guidelines. Future strategies for reducing ST and increasing integrated guidelines compliance are needed.

Cardiorespiratory fitness attenuates the association between fatness and cardiometabolic risk in Chinese children

Background

Childhood obesity tends to persist into adulthood, predisposing individuals to cardiometabolic risk (CMR). This study aims to investigate the mediating role of cardiorespiratory fitness (CRF) in the associations between multiple fatness indicators and individual CMR markers and clustered CMR-score, and explore sex differences.

Methods

We recruited 1,557 children (age: 8 to 10, male/female: 52.7%/47.3%) in September 2022 in Ningbo, China. Physical examinations, overnight fasting blood test, and CRF was evaluated. The CMR-score was calculated by summing age- and sex-specific z scores of four CMR markers, including mean arterial blood pressure, triglycerides, the total cholesterol to high-density lipoprotein cholesterol ratio, and homeostatic model assessment for insulin resistance. Generalized linear mixed models were used to identify the associations, mediation analyses were performed to dissect the function of CRF.

Results

Partial correlation analyses revealed positive associations between high fatness indicators (including body mass index [BMI], BMI z score, body fat mass index [BFMI] and waist-to-height ratio [WHtR]) and increased CMR markers, whereas high CRF was associated with decreased CMR markers (all P < 0.05). In the mediation analyses, CRF emerged as a partial mediator, attenuating the relationship between four fatness indicators and CMR-score. Specifically, CRF mediated 6.5%, 7.7%, 5.3%, and 12.5% of the association between BMI, BMI z score, BFMI, WHtR and CMR-score (all P < 0.001). And the mediating effects of CRF between WHtR and four individual CMR markers was particularly robust, ranging from 10.4% to 21.1% (all P < 0.05). What's more, CRF mediates the associations between WHtR and CMR-score more pronounced in girls than boys with a mediation effect size of 17.3% (P < 0.001).

Conclusion

In Chinese children, CRF partially mitigates the adverse effects of fatness on CMR, underscoring the significance of enhancing CRF in children.

Evaluating eight indicators for identifying metabolic syndrome in Chinese and American adolescents

BACKGROUND

Early intervention and diagnosis of Metabolic Syndrome (MetS) are crucial for preventing adult cardiovascular disease. However, the optimal indicator for identifying MetS in adolescent remains controversial.

METHODS

In total,1408 Chinese adolescents and 3550 American adolescents aged 12-17 years were included. MetS was defined according to the modified version for adolescents based on Adult Treatment Panel III (NCEP-ATP III) criteria. Areas under the curve (AUC) and corresponding 95% confidence interval (95% CI) of 8 anthropometric/metabolic indexes, such as waist circumference (WC), body mass index (BMI), a body shape index (ABSI), waist triglyceride index (WTI), were calculated to illustrate their ability to differentiate MetS. Sensitivity analysis using the other MetS criteria was performed.

RESULTS

Under the modified NCEP-ATP III criteria, WTI had the best discriminating ability in overall adolescents, with AUC of 0.922 (95% CI: 0.900-0.945) in Chinese and 0.959 (95% CI: 0.949-0.969) in American. In contrast, ABSI had the lowest AUCs. Results of sensitivity analysis were generally consistent for the whole Chinese and American population, with the AUC for WC being the highest under some criteria, but it was not statistically different from that of WTI.

CONCLUSIONS

WTI had relatively high discriminatory power for MetS detection in Chinese and American adolescents, but the performance of ABSI was poor.

IMPACT

While many studies have compared the discriminatory power of some anthropometric indicators for MetS, there are few focused on pediatrics. The current study is the first to compare the discriminating ability of anthropometric/metabolic indicators (WC, BMI, TMI, ABSI, WHtR, VAI, WTI, and TyG) for MetS in adolescents. WTI remains the optimal indicator in screening for MetS in adolescents. WC was also a simple and reliable indicator when screening for MetS in adolescents, but the performance of ABSI was poor. This study provides a theoretical basis for the early identification of MetS in adolescents by adopting effective indicators.

A proposed simplified definition of metabolic syndrome in children and adolescents: a global perspective

Metabolic syndrome (MetS) is becoming prevalent in the pediatric population. The existing pediatric MetS definitions (e.g., the International Diabetes Federation (IDF) definition and the modified National Cholesterol Education Program (NCEP) definition) involve complex cut-offs, precluding fast risk assessment in clinical practice.We proposed a simplified definition for assessing MetS risk in youths aged 6-17 years, and compared its performance with two existing widely used pediatric definitions (the IDF definition, and the NCEP definition) in 10 pediatric populations from 9 countries globally (n = 19,426) using the receiver operating characteristic (ROC) curve analyses. In general, the total MetS prevalence of 6.2% based on the simplified definition was roughly halfway between that of 4.2% and 7.7% estimated from the IDF and NCEP definitions, respectively. The ROC curve analyses showed a good agreement between the simplified definition and two existing definitions: the total area under the curve (95% confidence interval) of the proposed simplified definition for identifying MetS risk achieved 0.91 (0.89-0.92) and 0.79 (0.78-0.81) when using the IDF or NCEP definition as the gold standard, respectively.The proposed simplified definition may be useful for pediatricians to quickly identify MetS risk and cardiometabolic risk factors (CMRFs) clustering in clinical practice, and allow direct comparison of pediatric MetS prevalence across different populations, facilitating consistent pediatric MetS risk monitoring and the development of evidence-based pediatric MetS prevention strategies globally.

Prediction of cardiovascular disease risk by serum zinc and copper concentrations and anthropometric measurements

INTRODUCTION

We aimed to investigate the association between cardiovascular disease (CVD) and various anthropometric indices, as well as the serum levels of copper (Cu) and zinc (Zn), copper-zinc ratio (Cu/Zn ratio) and zinc-copper ratio (Zn/Cu ratio), in a large population sample from northeastern Iranian.

METHOD

9704 individuals aged 35 to 65 were enrolled in the first phase of the study. After a 10-year follow-up, 7560 participants were enrolled into the second phase. The variables used in this study included demographic characteristics, such as gender and age; biochemical parameters including: serum Zn, Cu, Cu/Zn ratio, and Zn/Cu ratio; anthropometric parameters including: waist circumference (WC), body mass index (BMI), and waist-to-hip ratio (WHR). The relationship between the aforementioned indices and CVD was examined using decision tree (DT) and logistic regression (LR) models.

RESULTS

A total of 837 individuals were diagnosed with CVD among the 7560 participants. LR analysis showed that BMI, age, WH zinc-copper ratio (Zn/Cu ratio), and serum Zn/Cu ratio were significantly associated the development of CVD in men, and WHR, age, BMI, serum Cu, and Cu/Zn ratio in women. DT analysis showed that, age was the most important predictor of CVD in both genders. 71% of women, older than 49 years, with a WHR≥ 0.89, serum Cu< 75 (µg/dl), BMI≥ 22.93 (kg/m2), and serum Cu≥ 14 (µg/dl), had the highest risk of CVD. In men, among those who were ≥ 53 years, with a WHR≥ 0.98, serum Zn/Cu ratio< 1.69, and BMI≥ 22.30, had the highest risk of CVD.

CONCLUSION

Among Iranian adult population, BMI, age, and WHR were one of the predictors of CVD for both genders. The Zn/Cu ratio was CVD predictor for men while Cu/Zn ratio was CVD predictor for women.

Utility of waist-to-height ratio, waist circumference and body mass index in predicting clustered cardiometabolic risk factors and subclinical vascular phenotypes in children and adolescents: A pooled analysis of individual data from 14 countries

AIMS

The clinical utility of waist-to-height ratio (WHtR) in predicting cardiometabolic risk factors (CMRFs) and subclinical markers of cardiovascular disease remains controversial. We aimed to compare the utility of WHtR with waist circumference (WC) and body mass index (BMI) in identifying children and adolescents (youths) at risk for cardiometabolic outcomes, including clustered CMRFs, high carotid intima-media thickness (cIMT), and arterial stiffness (assessed as high pulse wave velocity, PWV).

METHODS

We analyzed data from 34,224 youths (51.0 % boys, aged 6-18 years) with CMRFs, 5004 (49.5 % boys, aged 6-18 years) with cIMT measurement, and 3100 (56.4 % boys, aged 6-17 years) with PWV measurement from 20 pediatric samples across 14 countries.

RESULTS

WHtR, WC, and BMI z-scores had similar performance in discriminating youths with ≥3 CMRFs, with the area under the curve (AUC) (95 % confidence interval, CI)) ranging from 0.77 (0.75-0.78) to 0.78 (0.76-0.80) using the modified National Cholesterol Education Program (NCEP) definition, and from 0.77 (0.74-0.79) to 0.77 (0.74-0.80) using the International Diabetes Federation (IDF) definition. Similarly, all three measures showed similar performance in discriminating youths with subclinical vascular outcomes, with AUC (95 % CI) ranging from 0.67 (0.64-0.71) to 0.70 (0.66-0.73) for high cIMT (≥P95 values) and from 0.60 (0.58-0.66) to 0.62 (0.58-0.66) for high PWV (≥P95 values).

CONCLUSIONS

Our findings suggest that WHtR, WC, and BMI are equally effective in identifying at-risk youths across diverse pediatric populations worldwide. Given its simplicity and ease of use, WHtR could be a preferable option for quickly screening youths with increased cardiometabolic risk in clinical settings.

Tri-ponderal mass index and left ventricular hypertrophy in a cohort of caucasian children and adolescents with obesity

BACKGROUND

Pediatric obesity is a global emerging burden for society; among its health-related consequences there are hypertension (HTN) and left ventricular hypertrophy (LVH). Several anthropometric indices have been investigated for the early identification of cardiovascular risk in children. The aim of the present study was to assess whether tri-ponderal mass index (TMI) was associated with LVH in a cohort of Caucasian children and adolescents with obesity.

METHODS

In this observational study, 63 children and adolescents with obesity aged 7-to-16 years were enrolled. During outpatient visits, adiposity, and cardio-metabolic indices (BMI z-score, WHR, TMI, ABSI) were collected. All subjects underwent a 24-hour ambulatory blood pressure monitoring (ABPM) and transthoracic echocardiography.

RESULTS

Children and adolescents with obesity with LVH had significantly higher BMI z-score (p = 0.009), WHR (p = 0.006) and TMI (p = 0.026) compared to children without LVH. WC and WHR were the only indices significantly associated with left ventricular mass index (LVMI).

CONCLUSION

Left ventricular remodeling is associated with the cardio-metabolic risk markers WC and WHR, but not with the adiposity index TMI among children with obesity.

Timing of first abdominal operation in Crohn's disease based on a diagnostic model

This study aims to develop a clinical diagnostic model for assessing the need for initial abdominal surgery in patients diagnosed with Crohn's disease (CD) and create a nomogram to facilitate clinical decision-making. A total of 164 surgical CD patients and 230 control CD patients were included in this retrospective analysis. Least Absolute Shrinkage and Selection Operator (Lasso) regression and binomial logistic regression were employed to select clinical variables. The 394 CD patients were randomly allocated to a training set and a validation set in a 7:3 ratio. The filtered variables were used to establish a diagnostic model and nomogram in the training set, subsequently validated in the testing set. Decision Curve Analysis (DCA) and clinical impact curve were constructed to validate the clinical applicability of the model. Binomial logistic regression analysis identified seven clinical variables with a p-value less than 0.01, including Biomarker (B), Waist-to-Height Ratio (WHtR), Intestinal obstruction, Albumin (ALB), Crohn's Disease Activity Index (CDAI), Myocardial Flow Index (MFI), and C-reactive protein (CRP). These variables were utilized to establish the diagnostic model. Calibration curves showed good alignment, with a C-index of 0.996 in the training set and 0.990 in the testing set. DCA and clinical impact curve demonstrated that the diagnostic model had good clinical efficiency and could provide clinical benefits. A validated diagnostic model for determining the timing of the first abdominal operation in CD patients was established and evaluated, showing high discriminative ability, calibration, and clinical efficiency. It can be utilized by clinicians to assess the optimal timing for transitioning CD patients from medical treatment to surgical intervention, providing valuable references for individualized treatment decisions for CD patients.

Clinical Efficacy and Mechanism of Vitamin D2 in Treating Hashimoto's Thyroiditis

Objective

Hashimoto's thyroiditis (HT) is one of the most common autoimmune diseases, with the highest incidence rate among autoimmune thyroid disorders. Vitamin D2 may have therapeutic effects on HT. This study aimed to elucidate the molecular mechanisms underlying vitamin D2 therapy for HT.

Methods

Differentially expressed genes (DEGs) associated with vitamin D2-treated HT were identified, and the DEG-associated gene enrichment pathway was explored using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. The correlation between the hub genes and infiltrating immune cells was investigated, and the interactions among the hub genes and target drug and competing endogenous RNA (ceRNA; long non-coding RNA [lncRNA]-microRNA [miRNA]-messenger RNA [mRNA]) regulatory networks were determined.

Results

GO and KEGG enrichment analyses identified a total of 102 DEGs (6 upregulated and 96 downregulated) in the vitamin D2-treated group samples. The area under the curve values of the identified 10 hub genes was as follows: CCR1(0.920), CXCL1 (0.960), CXCL8 (0.960), EGR1 (0.960), FCGR3B (0.920), FOS (1.000), FPR1 (0.840), MMP9 (0.720), PTGS2 (0.960), and TREM1 (1.000). The immune enrichment scores of the mast cell (P = 0.008), neutrophil (P = 0.016), and plasmacytoid dendritic cell (P = 0.016) were significantly decreased in the vitamin D2-treated group (P < 0.05). The hub gene/drug regulatory network included 8 hub genes, 108 molecular drugs, and 114 interaction relationship pairs. The ceRNA regulatory network included 129 lncRNAs, 145 miRNAs, mRNAs (hub genes), and 324 interaction relationship pairs.

Conclusion

Vitamin D2 may play an immunomodulatory role by regulating the aforementioned immune-related molecules and immune cells, thereby improving its therapeutic effects on HT.

Risk of Obesity and Unhealthy Central Adiposity in Adolescents Born Preterm With Very Low Birthweight Compared to Term-Born Peers

Background: Early-life factors such as preterm birth or very low birthweight (VLBW) are associated with increased cardiovascular disease risk. However, it remains unknown whether this is due to an increased risk of obesity (unhealthy central adiposity) because studies have predominantly defined obesity based on BMI, an imprecise adiposity measure. Objective: Investigate if adolescents born preterm with VLBW have a higher risk of unhealthy central adiposity compared to term-born peers. Study Design: Cross-sectional analysis of data from a prospective cohort study of 177 individuals born preterm with VLBW (<1500 g) and 51 term-born peers (birthweight ≥2500 g). Individuals with congenital anomalies, genetic syndromes, or major health conditions were excluded. Height, weight, waist circumference, skin fold thickness, and dual energy X-ray absorptiometry body composition were measured at age 14 years. We calculated BMI percentiles and defined overweight/obesity as BMI ≥85th percentile for age and sex. We estimated the preterm-term differences in overweight/obesity prevalence and adiposity distribution with multivariable generalized linear models. Results: There was no difference in small for gestational age status or overweight/obesity prevalence. Compared to term, youth born preterm with VLBW had lower BMI z-score [β -0.38, 95% confidence limits (CL) -0.75 to -0.02] but no differences in adiposity apart from subscapular-to-triceps ratio (STR; β 0.18, 95% CL 0.08 to 0.28). Conclusions: Adolescents born preterm with VLBW had smaller body size than their term-born peers and had no differences in central adiposity except greater STR.

Unsupervised identification of cardiometabolic profiles among adolescents: findings from the PARIS birth cohort study

Metabolic syndrome (MetS) is known as a risk factor in cardiometabolic morbidity but there is no consensus on its definition for teenagers. We aimed to identify cardiometabolic health profiles and which parameters best discriminate them. K-means partitioning identified cardiometabolic profiles by sex using data on health measurements of 530 adolescents from the PARIS birth cohort. A discriminant analysis was performed. Cardiometabolic risk score and handgrip strength were also measured. Depending on definitions, MetS prevalence ranged from 0.2% to 1.3%. Two profiles were identified for the entire group and by sex: "healthy" and "at cardiometabolic risk." Weight and waist-to-height ratio or waist circumference explained more than 87% of the variance in the profile differentiation. The "at cardiometabolic risk" profiles included adolescents with overweight, a waist-to-height ratio over 0.5, and prehypertension. They had higher cardiometabolic risk scores and parents who were more likely to be overweight and have cardiometabolic diseases themselves. They also had higher birthweights, earlier adiposity-rebound and puberty ages, and lower relative handgrip strength.  Conclusion: The two profiles identified, based on cardiometabolic health, were associated with early indicators and handgrip strength. Results suggest that the waist-to-height ratio is a useful clinical tool for screening individuals at cardiometabolic risk and who therefore require clinical follow-up. What is Known: • Although there is a need for tools to assess cardiometabolic health during adolescence, there is no consensus on the definition of metabolic syndrome for this age group. What is Knew: • The findings suggest that waist-to-height ratio can serve as a simple and valuable clinical tool for screening individuals at cardiometabolic risk who may require clinical monitoring for early prevention of cardiovascular diseases.

There was a similar U-shaped nonlinear association between waist-to-height ratio and the risk of new-onset hypertension: findings from the CHNS

Background

The association between waist-to-height ratio (WHtR) with hypertension has not been adequately explained, so in this study we sought to clarify the predictive role of WHtR on the incidence of hypertension as well as the potential nonlinear associations in the general population.

Methods

In this large prospective cohort study, a total of 4,458 individuals from the China Health and Nutrition Survey (CHNS) were included in the analysis. Multivariate Cox regression analyses, subgroup analyses, receiver operator characteristic (ROC) and restricted cubic spline (RCS) analyses were used to examine the association of WHtR with the risk of new-onset hypertension.

Results

Hypertension occurred in 32.8% of participants during the maximum six-year follow-up period. Compared with the group with lower WHtR, the group with higher WHtR had a higher incidence of hypertension (p < 0.001). Multivariate Cox regression analysis showed that the risk of hypertension was 1.45 times higher in the high WHtR group than in the low WHtR group, and that the risk of hypertension increased by 30.4% for every 0.1 unit increase in WHtR (p < 0.001). Subgroup analyses also validated the stratified associations between WHtR and the risk of new-onset hypertension in most subgroups (p < 0.05). ROC analyses also revealed that WHtR was superior to body mass index in predicting new-onset hypertension (AUC: 0.626 vs. 0.607, p = 0.009). Further RCS analysis detected a nonlinear association between WHtR and risk of new-onset hypertension (P for nonlinearity <0.001).

Conclusion

WHtR was nonlinearly associated with the risk of new-onset hypertension in the general population.

Establishing international optimal cut-offs of waist-to-height ratio for predicting cardiometabolic risk in children and adolescents aged 6-18 years

BACKGROUND

Waist-to-height ratio (WHtR) has been proposed as a simple and effective screening tool for assessing central obesity and cardiometabolic risk in both adult and pediatric populations. However, evidence suggests that the use of a uniform WHtR cut-off of 0.50 may not be universally optimal for pediatric populations globally. We aimed to determine the optimal cut-offs of WHtR in children and adolescents with increased cardiometabolic risk across different countries worldwide.

METHODS

We used ten population-based cross-sectional data on 24,605 children and adolescents aged 6-18 years from Brazil, China, Greece, Iran, Italy, Korea, South Africa, Spain, the UK, and the USA for establishing optimal WHtR cut-offs. We performed an external independent test (9,619 children and adolescents aged 6-18 years who came from other six countries) to validate the optimal WHtR cut-offs based on the predicting performance for at least two or three cardiometabolic risk factors.

RESULTS

Based on receiver operator characteristic curve analyses of various WHtR cut-offs to discriminate those with ≥ 2 cardiometabolic risk factors, the relatively optimal percentile cut-offs of WHtR in the normal weight subsample population in each country did not always coincide with a single fixed percentile, but varied from the 75th to 95th percentiles across the ten countries. However, these relatively optimal percentile values tended to cluster irrespective of sex, metabolic syndrome (MetS) criteria used, and WC measurement position. In general, using ≥ 2 cardiometabolic risk factors as the predictive outcome, the relatively optimal WHtR cut-off was around 0.50 in European and the US youths but was lower, around 0.46, in Asian, African, and South American youths. Secondary analyses that directly tested WHtR values ranging from 0.42 to 0.56 at 0.01 increments largely confirmed the results of the main analyses. In addition, the proposed cut-offs of 0.50 and 0.46 for two specific pediatric populations, respectively, showed a good performance in predicting ≥ 2 or ≥ 3 cardiometabolic risk factors in external independent test populations from six countries (Brazil, China, Germany, Italy, Korea, and the USA).

CONCLUSIONS

The proposed international WHtR cut-offs are easy and useful to identify central obesity and cardiometabolic risk in children and adolescents globally, thus allowing international comparison across populations.

Height-Corrected Definition of Metabolic Syndrome Is a Simple and Effective Method for Identifying Insulin Resistance and Low-Grade Inflammation in Adolescents: Metabolic Syndrome in Adolescents

The purpose of this study was to evaluate the feasibility of the height-corrected definition of metabolic syndrome(MetS) in adolescents. A retrospective study was conducted on US adolescents aged 12 to 17 years. Waist-to-height ratio and blood pressure-to-height ratio were substituted for waist circumference and blood pressure when defining MetS in adolescents. The proportions of insulin resistance of adolescents with 1 (30.1%), 2 (50.7%), and ≥3 components (77.8%) of MetS were 2.578 (P < .001), 6.882 (P < .001), and 23.992 (P < .001) times than the proportion of adolescents without the component of MetS (14.2%). The proportions of low-grade inflammation of adolescents with 1 (3.4%), 2 (5.3%), and ≥3 components (14.4%) of MetS were 2.050 (P = .106), 3.699 (P = .005), and 10.664 (P < .001) times than the proportion of adolescents without the component of MetS (1.7%). This study demonstrates that height-corrected definition of MetS is a simple and accurate method for identifying insulin resistance and low-grade inflammation in adolescents.

Precursors of insulin resistance underlying periodontitis in adolescents aged 17-18 years

OBJECTIVE

To investigate the association between insulin resistance markers and periodontitis in adolescents, analyzing confounder variables and the adiposity as a mediator.

METHODS

This is population-based study is representative of adolescents aged 17-18 years from public schools in São Luís, Brazil (n = 405). Insulin resistance was assessed using the Model of Assessment of the Homeostasis of the Insulin Resistance Index (HOMA-IR) and its percussor triglycerides/HDL-cholesterol ratio (TG/HDL-c). The outcome was Initial Periodontitis, a latent variable estimated by the common variance shared among bleeding on probing, probing depth ≥ 4 mm, and clinical attachment loss ≥ 4 mm. The association between insulin resistance and Initial Periodontitis was modeled via pathways triggered by socioeconomic status, smoking, alcohol, and Adiposity, using structural equation modeling.

RESULTS

Higher TG/HDL-c was directly associated with higher Initial Periodontitis (standardized coefficient [SC] = 0.130, p < 0.001). HOMA-IR was not associated with periodontal outcome (SC = 0.023, p = 0.075), but it was with Adiposity (SC = 0.495, p < 0.001). Higher TG/HDL-c was associated with Adiposity (SC = 0.202, p < 0.001).

CONCLUSION

The insulin resistance markers were associated with early signs of periodontal breakdown among adolescents, suggesting a possible relationship between diabetes and periodontitis commences early in life.

Novel Anthropometric Indices as Screening Tools for Obesity: A Study on Healthy Iranians

Background and Aims

Upper body fat distribution is more related to cardiometabolic diseases than central obesity. Neck circumference (NC) and neck-to-height ratio (NHtR) are two indicators of upper body obesity that are affordable, easy to obtain, highly reproducible, and more practical in the crowded health centers than the classic anthropometric indices.

Methods

18-65-year-old individuals with no past medical history were included. After obtaining written informed consent, they were screened for hypertension, high blood glucose, and other abnormal laboratory results. Data were analyzed using SPSS and Mann-Whitney U test, Chi square test, Spearman's correlation coefficient, and ROC curve.

Results

In our 2,812 participants, NC had the lowest area under the curve (AUC) in both male and female obese and overweight subjects. NHtR and hip circumference (HC) had the highest AUC in men and women with obesity, respectively. The highest sensitivity for overweight men and women belonged to waist circumference (WC) and waist-to-height ratio (WHtR), respectively, and for both males and females with obesity, NHtR had the highest sensitivity. The cutoff point of NHtR had the same value for males and females. HC and NHtR had the highest positive likelihood ratio (PLR) for obesity in men. In addition, HC and WC had the highest PLR for obesity in women.

Conclusion

In this study, we revealed that NC had the lowest and NHtR and HC had the highest predictive value for obesity. Furthermore, for both males and females with obesity, NHtR had the highest sensitivity. HC had the highest PLR for obesity in both genders. Our results warrant prospective studies to evaluate the role of NHtR and other novel anthropometric indices in the risk of cardiometabolic diseases.

Protocol Study: Resistance Training Program, Nutritional, Sleep, and Screen Use Recommendations in Schoolchildren from Educational Centers in the Extreme South of Chile

BACKGROUND

Childhood obesity has tripled, reaching critical levels of malnutrition. This factor is directly associated with a poorer health-related quality of life of the child and adolescent population. This article presents the study protocol of the project "Strong schoolchildren with a healthy lifestyle" (EF-Salud), which seeks to analyze the effects of a multicomponent program based on muscle strength exercises, sleep nutritional recommendations, and the use of screens in Chilean educational centers with extremely cold weather.

METHODS

The study protocol of a randomized controlled trial with a pre- and post-test conducted according to the CONSORT statement is reported. The total sample (n = 144) will be schoolchildren from six different school years, four of which will perform an intervention and two control. Intervention group 1 (from two different school years) will receive a muscular strength exercise program in the classroom once a day from Monday to Friday for six months and nutritional, sleep, and use of screens recommendations once a week. Intervention group 2 (from two different school years) will receive a program of nutritional, sleep, and use of screens recommendations once per week for six months. The control group (from two different school years) will carry out their usual school day in relation to physical education classes. Before and after the intervention, the investigators will evaluate the cardiovascular risk, physical condition, and lifestyle related to sleep and use of screens.

EXPECTED RESULTS

The schoolchildren in intervention group 1 will obtain significant results in increased strength, decreased cardiovascular risk, improved sleep habits, and fewer hours of screen use compared to the other two groups.

The weight-adjusted-waist index predicts all-cause and cardiovascular mortality in general US adults

BACKGROUND

The authors examined the relationship between Weight-adjusted Waist Index (WWI) and all-cause and cardiovascular mortality among adults in the US.

METHODS

This prospective cohort study included 26,882 individuals who participated in the National Health and Nutrition Examination Survey (NHANES) from 2005 through 2014. WWI was calculated as waist circumference divided by the square root of weight. The main outcomes of this study were all-cause mortality and cardiovascular mortality. Mortality status and cause of death were determined by NHANES-linked National Death Index records through December 31, 2015. Cox proportional hazard models and Kaplan-Meier analysis were used to estimate Hazard Ratios (HR) and 95% CIs for mortality for all causes and cardiovascular diseases.

RESULTS

A total of 26,882 participants with a mean WWI of 10.89 ± 0.01, of whom 49.23% were male. The average follow-up time was 68.95 ± 1.07 months, and 1870 participants were determined as deceased (4.99%), including 349 cardiovascular death (0.88%). The Kaplan-Meier analysis demonstrated a significant difference in all-cause and cardiovascular mortality between patients with WWI <11.33 and ≥11.33 (both log-rank test p < 0.0001). The fully adjusted Cox proportional hazard model indicated that a higher WWI level (≥ 11.33) was associated with an increased 95% risk for cardiovascular mortality (HR = 1.95, 95% CI 1.30‒2.93) and 68% risk for all-cause death (HR = 1.68, 95% CI 1.41‒2.00) compared with the counterparts.

CONCLUSIONS

Elevated WWI levels were associated with a higher risk of cardiovascular mortality and all-cause mortality independently.

Development of Data Mining Algorithms for Identifying the Best Anthropometric Predictors for Cardiovascular Disease: MASHAD Cohort Study

INTRODUCTION

Many studies have been published to assess the best anthropometric measurements associated with cardiovascular diseases (CVDs), but controversies still exist.

AIM

Investigating the association between CVDs and anthropometric measurements among Iranian adults.

METHODS

For a total population of 9354 aged 35 to 65, a prospective study was designed. Anthropometric measurements including ABSI (A Body Shape Index), Body Adiposity Index (BAI), Body Mass Index (BMI), Waist to Height Ratio (WHtR), Body Round Index (BRI), HC (Hip Circumference), Demispan, Mid-arm circumference (MAC), Waist-to-hip (WH) and Waist Circumference (WC) were completed. The association between these parameters and CVDs were assessed through logistic regression (LR) and decision tree (DT) models.

RESULTS

During the 6-year follow-up, 4596 individuals (49%) developed CVDs. According to the LR, age, BAI, BMI, Demispan, and BRI, in male and age, WC, BMI, and BAI in female had a significant association with CVDs (p-value < 0.03). Age and BRI for male and age and BMI for female represent the most appropriate estimates for CVDs (OR: 1.07, (95% CI: 1.06, 1.08), 1.36 (1.22, 1.51), 1.14 (1.13, 1.15), and 1.05 (1.02, 1.07), respectively). In the DT for male, those with BRI ≥ 3.87, age ≥ 46 years, and BMI ≥ 35.97 had the highest risk to develop CVDs (90%). Also, in the DT for female, those with age ≥ 54 years and WC ≥ 84 had the highest risk to develop CVDs (71%).

CONCLUSION

BRI and age in male and age and BMI in female had the greatest association with CVDs. Also, BRI and BMI was the strongest indices for this prediction.

Skeptical Look at the Clinical Implication of Metabolic Syndrome in Childhood Obesity

Metabolic syndrome (MetS) is defined by a cluster of several cardio-metabolic risk factors, specifically visceral obesity, hypertension, dyslipidemia, and impaired glucose metabolism, which together increase risks of developing future cardiovascular disease (CVD) and type 2 diabetes mellitus (T2D). This article is a narrative review of the literature and a summary of the main observations, conclusions, and perspectives raised in the literature and the study projects of the Working Group of Childhood Obesity (WGChO) of the Italian Society of Paediatric Endocrinology and Diabetology (ISPED) on MetS in childhood obesity. Although there is an agreement on the distinctive features of MetS, no international diagnostic criteria in a pediatric population exist. Moreover, to date, the prevalence of MetS in childhood is not certain and thus the true value of diagnosis of MetS in youth as well as its clinical implications, is unclear. The aim of this narrative review is to summarize the pathogenesis and current role of MetS in children and adolescents with particular reference to applicability in clinical practice in childhood obesity.

Comparative analyses of surrogates of metabolic syndrome in children and adolescents with metabolically healthy obesity vs. metabolically unhealthy obesity according to Damanhoury's criteria

OBJECTIVES

Metabolically healthy obesity (MHO) has been reported with varying frequencies in children. The reasons of metabolically healthy phenotype in some obese subjects are unclear. Our aim was to identify the frequency of MHO in obese subjects, to assess the potential associations of demographic characteristics, serum uric acid, alanine transaminase (ALT), pediatric nonalcoholic fatty liver disease fibsosis score probability (PNFS p) with MHO status and to evaluate the differences between MHO and metabolically unhealthy obesity (MUO) with regard to metabolic syndrome surrogates.

METHODS

251 consecutive obese subjects (125 females) aged 7-18 years were included. Subjects were classified as having MHO according to Damanhoury's criteria. Several metabolic variables were measured, PNFS p was calculated by using the formula: z=1.1+(0.34*sqrt(ALT))+ (0.002*ALP)-(1.1*log(platelets)-(0.02*GGT).

RESULTS

Median age of the subjects was 12.5 yr (range: 7.0-17.0 yr). The frequency of MHO was 41 %. Subjects with MHO were significantly younger, had lower waist circumference (WC) and waist height ratio (WHtR) and lower HOMA-IR than those without MHO(p<0.05 for all). Frequencies of hyperuricemia, hypertransaminasemia, hepatosteatosis and PNFS p values≥8 were similar betwen the groups. When putatively influential factors associated with MHO status were assessed with logistic regression analysis, only WC(β=1.03) and HOMA-IR(β=1.166) emerged as significant factors(Nagelkerke R2=0.142). None of the investigated demographic factors were associated with MHO status.

CONCLUSIONS

We found a remarkably high frequency of MHO status. Nevertheless, the absence of decreased frequencies of hyperuricemia, hypertransaminasemia and PNFS in subjects with MHO may suggest the need to reconsider the validity of the criteria defining MHO.

Hypertriglyceridemic waist phenotype, hypertriglyceridemic waist-to-height ratio phenotype and abnormal glucose metabolism in adolescents

OBJECTIVE

The purpose of this study was to evaluate the relationship between hypertriglyceridemic waist (HW) phenotype,hypertriglyceridemic waist-to-height ratio (HWHtR) phenotype and abnormal glucose metabolism in adolescents.

METHODS

A secondary analysis was conducted on 2626 adolescents aged 12-19 years in United States. Abnormal glucose metabolism was defined as fasting plasma glucose ≥ 5.6 mmol/L or oral glucose tolerance test 2-h plasma glucose ≥ 7.8 mmol/L or glycohemoglobin A1c ≥ 5.7% or a previous diagnosis of diabetes. The HW phenotype was defined as triglyceride(TG) concentrations ≥ 1.47 mmol/L and waist circumference (WC) ≥ 90th percentile. The HWHtR phenotype was defined as TG concentrations ≥ 1.47 mmol/L and waist-to-height ratio (WHtR) ≥ 0.5.

RESULTS

621(23.6%) adolescents had abnormal glucose metabolism. The prevalences of abnormal glucose metabolism were 22.7% and 40.6% in adolescents without and with HW phenotype. The prevalences of abnormal glucose metabolism were 22.4% and 38.6% in adolescents without and with HWHtR phenotype. Adolescents with HWHtR phenotype were more likely to have abnormal glucose metabolism (OR = 1.548, P = 0.010). The levels of homeostasis model assessment insulin resistance and β cell fuction index were higher in adolescents with HWHtR phenotype than in adolescents without HWHtR phenotype (P < 0.001).

CONCLUSION

The study demonstrates that HWHtR phenotype was closely associated with an increased risk of abnormal glucose metabolism in adolescents. Adolescents with HWHtR phenotype had worsen insulin resistance and increased insulin secretion as a result of compensation.

IMPACT STATEMENT

The study provided a simple method, HWHtR phenotype, for evaluating the status of glucose metabolism in adolescents.

Predictive ability of traditional and novel anthropometric measurement indices for cardio-metabolic diseases in Chinese adults: China Health and Nutrition Survey (CHNS) cohort study

BACKGROUND AND AIMS

Cardio-metabolic diseases has been shown to be strongly associated with obesity. The aim of this study was to compare the predictive value of traditional and novel anthropometric measurement indices for cardio-metabolic diseases risk and evaluate whether new indicators can provide important information in addition to traditional indicators.

METHODS AND RESULTS

China Health and Nutrition Survey (CHNS) data were obtained for this study. Baseline information for healthy participants was gathered from 1997 to 2004. The incidence of cardio-metabolic diseases was collected from 2009 to 2015 for cohort analysis. The predictive ability of each index for the risk of cardio-metabolic diseases was evaluated with time-dependent ROC analysis. Body mass index (BMI) showed the greatest predictive ability for cardio-metabolic disease incidence among all traditional and novel indices (Harrell's C statistic (95% CI): 0.7386 (0.7266-0.7507) for hypertension, 0.7496 (0.7285-0.7706) for diabetes, 0.7895 (0.7593-0.8196) for stroke and 0.7581 (0.7193-0.7969) for myocardial infarction). The addition of novel indices separately into the BMI model did not improve the predictive ability. Novel anthropometric measurement indices such as a body shape index (ABSI), abdominal volume index (AVI) and triponderal mass index (TMI), had a certain prediction ability for adults with BMI <24 kg/m² compared to those with BMI ≥24 kg/m².

CONCLUSION

No strong evidence supports novel anthropometric measurement indices were better than BMI in the prediction of cardio-metabolic diseases incidence among Chinese adults. Novel anthropometric measurement indices, mainly for abdominal obesity, may have a high predictive effect for adults with BMI <24 kg/m².

Overfat cutoffs and the optimal combination of body fat indices for detecting cardiometabolic risk among school-aged children

OBJECTIVE

This study aimed to develop cutoffs and the optimal combination for body fat indices for screening cardiometabolic risk (CMR) among the pediatric population.

METHODS

This cross-sectional study consisted of 8710 (50.3% boys) Chinese children aged 6 to 18 years. Body fat indices, including fat mass index (FMI), body fat percentage, trunk to leg fat ratio (TLR), and android to gynoid fat ratio, were derived from dual-energy x-ray absorptiometry scans. The area under the receiver operating characteristic curve was used to determine the best combination and optimal cutoffs of body fat indices to identify CMR.

RESULTS

Compared with anthropometry-based obesity measures, i.e., BMI and waist circumference, the FMI + TLR combination presented statistically higher area under the receiver operating characteristic curve values for discriminating CMR and its clustering. The optimal overfat cutoffs of FMI and TLR were respectively determined at the 75th percentile in boys and at the 80th percentile of FMI and the 75th percentile of TLR in girls. Moreover, simplified thresholds derived from age-group-merged cutoffs showed similar performance as optimal cutoffs in detecting CMR.

CONCLUSIONS

Both the optimal and simplified overfat cutoffs were provided for the Chinese pediatric population. The use of FMI and TLR together allows for adequate screening of CMR and its clustering.

Transform-Us! cluster RCT: 18-month and 30-month effects on children's physical activity, sedentary time and cardiometabolic risk markers

OBJECTIVE

To test the efficacy of the Transform-Us! school- and home-based intervention on children's physical activity (PA), sedentary behaviour (SB) and cardiometabolic risk factor profiles.

METHODS

A 30-month 2×2 factorial design cluster randomised controlled trial delivered in 20 primary schools (148 Year 3 classes) in Melbourne, Australia (2010-2012), that used pedagogical and environmental strategies to reduce and break up SB, promote PA or a combined approach, compared with usual practice. Primary outcomes (accelerometry data; n=348) were assessed at baseline, 18 and 30 months. Secondary outcomes included body mass index (BMI) and waist circumference (WC) (n=564), blood pressure (BP) (n=537) and biomarkers (minimum n=206). Generalised linear mixed models estimated the interactive effects of the PA and SB interventions on the outcomes. If there was no interaction, the main effects were assessed.

RESULTS

At 18 months, there were intervention effects on children's weekday SB (-27 min, 95% CI: -47.3 to -5.3) for the PA intervention, and on children's average day PA (5.5 min, 95% CI: 0.1 to 10.8) for the SB intervention. At 30 months, there was an intervention effect for children's average day SB (-33.3 min, 95% CI: -50.6 and -16.0) for the SB intervention. Children's BMI (PA and SB groups) and systolic BP (combined group) were lower, and diastolic BP (PA group) was higher. There were positive effects on WC at both time points (SB intervention) and mixed effects on blood parameters.

CONCLUSIONS

The Transform-Us! PA and SB interventions show promise as a pragmatic approach for reducing children's SB and adiposity indicators; but achieving substantial increases in PA remains challenging.

TRIAL REGISTRATION

ISRCTN83725066; ACTRN12609000715279.

Reference percentiles for tri-ponderal mass index and its association with general and abdominal obesity among Iranian children and adolescents: A report from the SHED LIGHT study

BACKGROUND

The body mass index (BMI) has some limitations in identifying obesity, particularly among children and adolescents.

OBJECTIVES

We sought to determine the reference percentiles of tri-ponderal mass index (TMI) for Iranian population, and its relation to BMI, waist circumference (WC), and waist circumference-to-height ratio (WHtR).

METHODS

Baseline characteristics for 14 641 children and adolescents were applied. The area under the characteristics (AUC) curve and optimal cut-off points for TMI were used to define the accuracy of TMI for discriminating general and central obesity compared to other anthropometric measurements.

RESULTS

TMI levels remained stable from 6 to 18 years with a small range of difference. The highest AUCs for discriminating obesity according to BMI and WHtR ≥0.5 from non-obese subjects were related to TMI (0.980) and TMI (0.912), respectively, and these findings were similar for both sexes. Moreover, the AUC for TMI to discriminate central obesity by WHtR was higher than that for BMI (0.912 vs. 0.833, p < .001), and this difference was similar among sex and age groups. The optimal value of TMI for discriminating general obesity, obesity by WC, and obesity by WHtR were 15.2 (sensitivity 96.2 and specificity 89.8), 15 (sensitivity 86.9 and specificity 79.9), and 13.9 (sensitivity 85.1 and specificity 81.5), respectively.

CONCLUSIONS

TMI discriminated central obesity by WHtR more accurately than obesity by BMI among Iranian children and adolescents irrespective of sex. Besides it remained relatively constant across age- and sex-specific groups providing a single optimal cut-off point for screening obesity during childhood and adolescence.

Role of Insulin Resistance as a Mediator of the Relationship between Body Weight, Waist Circumference, and Systolic Blood Pressure in a Pediatric Population

Excess weight and high waist circumference (WC) are associated with increased blood pressure (BP), starting from the pediatric age. Insulin resistance is associated with elevated BP in childhood. The aim of the study was to assess the role of insulin resistance in mediating the relationship between body mass index (BMI), WC, and BP values in a pediatric population referred to a cardio-pediatric center for the presence of one or more cardiovascular risk factors. In 419 children (mean age 10.7 [standard deviation, SD 2.5] years), the following parameters were collected both in basal conditions and after 18.6 (SD 9.3) months of follow-up during which a treatment based on lifestyle and dietary modifications was given: systolic and diastolic BP (SBP and DBP), WC, plasma glucose, and insulin values. The HOMA (Homeostasis Model Assessment)-index was considered as an expression of insulin resistance. At baseline there was a significant correlation between HOMA-index and SBP z-score (β = 0.081, p = 0.003), and insulin resistance was a mediator of the relationship between BMI and SBP z-score (p = 0.015), and between waist circumference to height (WtHr) and SBP z-score (p = 0.008). The effect of BMI z-score modifications on SBP z-score changes from baseline to follow-up was totally mediated by HOMA-index changes (p = 0.008), while HOMA-index only partially mediated the effect of WtHr modifications on SBP z-score changes (p = 0.060). Our study strongly suggests that, in a pediatric population at cardiovascular risk, the HOMA-index is an important mediator of the relationship between BMI, WC and SBP.

Effects on Children's Physical and Mental Well-Being of a Physical-Activity-Based School Intervention Program: A Randomized Study

This study aimed to evaluate the effectiveness of physically active breaks of a total duration of 10 min a day, introduced during curricular lessons, together with a 10 min physical activity intervention during the daily school recess period on obesity prevention, fitness, cognitive function, and psychological well-being in school-aged children. A sample of 310 children (139 boys vs. 171 girls), aged between 8 and 10 years (9.82 ± 0.51), was selected. Our strategy was implemented over a 6-month period and the participants were randomly assigned to either the intervention group (n = 157) or the non-intervention (control) group (n =153). In the intervention group, a significant decrease (p < 0.05) in body mass index, waist circumference, waist-height ratio, and relative body fat mass was achieved after the intervention (T1) compared to the values measured before intervention (T0); in the control group, no differences emerged between T0 and T1 for any of the parameters considered. We found a significant increase in the intervention group in standing long jump, Ruffier, and sit and reach test scores (p < 0.001 for all). At T0, cognitive test scores did not differ between the girls and boys or between the intervention and control groups; instead at T1, significant differences were observed in the two groups regarding the total number of responses and the concentration performance scores (p < 0.001). Consistently, in the intervention group, well-being levels significantly increased between T0 and T1 (p < 0.001). Finally, the intervention had significant effects on the children regardless of gender. We may therefore conclude that schools should create more opportunities for teachers and students to introduce intervention strategies to promote regular PA during school recess.

Optimal cut-off value of waist circumference-to-height ratio to predict central obesity in children and adolescents: A systematic review and meta-analysis of diagnostic studies

Introduction

Waist circumference-to-height ratio (WHtR) is a simple anthropometric index with good screening power and fast interpretation for early detection of childhood abdominal obesity. This systematic review and meta-analysis aims to determine the best cut-off value of WHtR to use in clinical setting.

Methods

Comprehensive searches were conducted in PubMed, Scopus, and Web of Science by the end of March 2021. Observational studies investigated the best WHtR cut-off to detect abdominal obesity in children and adolescents were included. Thirteen articles (n = 180,119) were included in this systematic review and eight documents were included in the meta-analysis.

Results

The overall optimal cut-off was 0.49 with pooled sensitivity, specificity and diagnostic odds ratio (DOR) of 0.93 (95% confidence interval (CI): 0.93-0.96), 0.88 (95% CI: 0.85-0.91) and 102.6 (95% CI: 50.7-207.5), respectively. The optimal WHtR cut-off to predict abdominal obesity in girls and boys were both 0.49.

Discussion

The current study shows that we could use this cut-off as a simple index for predicting abdominal obesity in children and adolescents without the need for any charts in practice.

Triponderal mass index is as strong as body mass index in the determination of obesity and adiposity

OBJECTIVE

In determining obesity and body adiposity, triponderal mass index (TMI) is as strong an anthropometric measurement as body mass index (BMI). The aim of this study was to develop TMI reference values for Turkish children and adolescents and compare TMI with BMI according to body adiposity and obesity indices.

METHODS

Data from the DAMTCA-II (Determination of Anthropometric Measurements of Turkish Children and Adolescents II) study were used in this cross-sectional study. Data from 4330 children (1931 boys, 2399 girls) ages 6 to 17 y were evaluated, and the TMI percentile values were produced. The predictive power of TMI and BMI for obesity and overweight were done for waist circumference, waist/height ratio, body fat percentage, and upper arm fat area, which are different parameters used to determine body adiposity.

RESULTS

The 3rd, 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th, and 97th TMI percentiles and mean values were calculated for all children's age and sex. TMI cutoff values were calculated by receiver operating characteristic analysis regarding waist/height ratio 0.5, waist circumference ≥90 percentile, arm fat area ≥85 percentile, and body fat percentage ≥85. TMI and BMI area under the curve values were similar for each of these four measurements. TMI was as robust an index as BMI in demonstrating obesity and adiposity for all age groups in boys and girls. It was concluded that the values >90th percentile (median 15.8 kg/m³) in girls aged ≤10 y, 95th percentile (median 16.2 kg/m³) in girls aged >10 y, >85th percentile (median 14.9 kg/m³) in boys aged ≤12 y and 75th percentile (median value 14.5 kg/m³) in boys aged >12 y are critical values for TMI when evaluating adiposity and obesity.

CONCLUSIONS

We considered that TMI is as effective as BMI in terms of waist/height ratio, waist circumference, arm fat area, and body fat percentage in determining overweight and obesity in children. The ages at which TMI showed distinct variation were determined for both sexes.

Physical fitness mediates and predicts for high blood pressure among children in relation to weight status

Background

Pediatric hypertension contributes to adulthood hypertension and target organ damage. Obesity is a well-known predictor for pediatric hypertension; however, the relationship between physical fitness and blood pressure (BP) is unclear among children. This study aimed to compare the differences in demographics, anthropometrics, and physical fitness across BP subgroups and investigate whether physical fitness was related to pediatric hypertension independent of weight status.

Methods

This quantitative, cross-sectional study investigated demographic, anthropometric, physical fitness, and BP measures among 360 healthy school-aged children. Continuous variables were compared across BP subgroups with the one-way analysis of variance. Mediation and moderation analyses were used to explore the mechanism. Multivariable regression models were used to assess independent associations for hypertension.

Results

There were 177 (49.2%), 37 (10.3%), and 146 (40.6%) children in the normotensive, elevated BP, and hypertensive subgroups, respectively. The hypertensive subgroup had higher body mass index (BMI) and waist/height ratio percentiles and performed worse in 800-m run, standing long jump (SLJ), and 1-min sit-ups than the normotensive subgroup. Furthermore, the 800-m run percentile (total effect: β = 0.308, standard error = 0.044, p < 0.001) and sit and reach percentile (total effect: β = 0.308, standard error = 0.044, p < 0.001) mediated the relationship between the BMI percentile and systolic BP percentile; the SLJ percentile was directly associated with the diastolic BP percentile (β,-0.197, 95% confidence interval,-0.298-0.097; p < 0.001). The parsimonious model of multivariable regression models revealed that the SLJ percentile (adjusted exp (β), 0.992, 95% confidence interval, 0.985-0.999; p = 0.042) and BMI percentile (adjusted exp (β), 1.024, 95% confidence interval, 1.016-1.032; p < 0.001) were two independent predictors for pediatric hypertension.

Conclusion

Physical fitness mediates the relationship between anthropometric and BP measures. The SLJ percentile is associated with pediatric hypertension independent of the BMI percentile. Proactive screening and health promotion for not only healthy weight status but also good physical fitness may be beneficial for BP control among school-aged students.

Trends in elevated waist-to-height ratio and waist circumference in U.S. adults and their associations with cardiometabolic diseases and cancer, 1999-2018

Introduction

Although waist-to-height ratio (WHtR) has established association with cardiometabolic disease, the trend of changes in elevated WHtR among general population have not been examined adequately.

Methods

This study examined the prevalence of elevated WHtR and waist circumference (WC) and their trends over time using Joinpoint regression models among adults who participated in the United States National Health and Nutrition Examination Survey (U.S. NHANES) 1999-2018. We performed weighted logistic regression to identify the association between central obesity subtypes and the prevalence of comorbidities, including diabetes, chronic kidney disease, hypertension, cardiovascular disease, and cancer.

Results

The prevalence of elevated WHtR has increased from 74.8% in 1999-2000 to 82.7% in 2017-2018 while elevated WC also increased from 46.9% in 1999-2000 to 60.3% in 2017-2018. Men, older adults, former smokers, and people with lower education levels were more likely to have elevated WHtR. A total of 25.5% of American adults had normal WC but elevated WHtR, and they had a significantly higher chance of suffering from diabetes (odds ratio [OR] = 2.06 [1.66, 2.55]), hypertension (OR = 1.75 [1.58, 1.93]) and CVD (OR = 1.32 [1.11, 1.57]).

Discussion

In conclusion, the burden of elevated WHtR and WC have been increasing among U.S. adults throughout the years, and the changes have been more significant across most subgroups. It is also notable that approximately a quarter of the population had normal WC but elevated WHtR, which had increased likelihood of having cardiometabolic diseases, especially diabetes. Future clinical practices should pay more attention to this subgroup of the population with overlooked health risks.

Correlation of body mass index and waist to height ratio with cardiovascular risk factors in Colombian preschool and school children

Objective

To analyze the agreement between body mass index (BMI) and waist-to-height Ratio (WHtR) to identify preschool and school children with cardiovascular risk factors (CRFs).

Methods

Three-hundred-twenty-one kids were divided into preschool (3-5 years) and school children (6-10 years). BMI was used to classify children as overweight or obese. Abdominal obesity was defined with a WHtR ≥0.50. Fasting blood lipids, glucose and insulin were measured, and the homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. The presence of CRFs and multiple non-waist circumference (non-WC) metabolic syndrome factors (MetS-Factors) [high HOMA-IR, high triglycerides and low high-density lipoprotein cholesterol (HDL-C)] were analyzed.

Results

One-hundred-twelve preschool and 209 school children were evaluated. WHtR ≥0.50 classified abdominal obesity in more than half of the preschool children, exceeding those classified with overweight+obesity by BMI (59.5% vs. 9.8%; p<0.001). There was no agreement between WHtR and BMI to identify preschool kids with CRFs and multiple non-WC MetS-Factors (kappa: 0.0 to 0.23, p>0.05). There were similar proportions of school children classified with abdominal obesity by the WHtR and overweight+obesity by the BMI (18.7% vs. 24.9%; p>0.05). There was substantial agreement between WHtR and BMI to identify school children with high total cholesterol values, low-density lipoprotein cholesterol (LDL-C), triglycerides, non-HDL-C, insulin, HOMA-IR, low HDL-C values, and the presence of multiple non-WC MetS-Factors (kappa: 0.616 to 0.857, p<0.001).

Conclusion

In preschool children WHtR ≥0.5 disagree with BMI results, but in school kids, it has good agreement with the BMI to classify the children´s nutritional status and to identify those with CRFs.

Comparison of Glycosylated Haemoglobin, Blood Pressure, and Anthropometric Measurements Depending on Gender and Bodyweight State in Adolescents

Background/Objective: The greatest anthropometric and physiological changes occur during adolescence. Assessment of growth patterns is necessary to prevent future health risks. Aims: To describe the values of glycosylated haemoglobin (HbA1c), systolic (SBP) and diastolic (DBP) blood pressure, triceps skinfold, and abdominal circumference according to gender and age (between 12 and 17 years), as well as explore the differences between body weight conditions. Methods: A descriptive cross-sectional study was carried out, including 4130 adolescents between 12 and 17 years old. SBP and DBP, HbA1c, triceps skinfold, and abdominal circumference were evaluated. Results: Significant differences were observed between males and females for HbA1c (p < 0.001), SBP (p < 0.001), triceps curl (p < 0.001), and abdominal circumference (p < 0.001), independently of the age group. Regardless of gender and age groups, significant differences were observed between overweight/obese and normal-weight adolescents in SBP (p < 0.001), DBP (p < 0.001 to 0.009), triceps skinfold (p < 0.001), and abdominal perimeter (p < 0.001). Conclusions: Our findings revealed higher SBP, DBP, triceps skinfold, and abdominal circumference in overweight/obese adolescents compared to normal-weight adolescents in both genders.

Peripheral blood mononuclear cells-expressed miRNA profiles derived from children with metabolic-associated fatty liver disease and insulin resistance

BACKGROUND

miRNA have been proposed as potential biomarkers of metabolic diseases.

OBJECTIVES

To identify potential miRNA biomarkers of early metabolic-associated fatty liver disease (MAFLD) and/or insulin resistance (IR) in preadolescent children.

METHODS

A total of 70 preadolescents, aged 8.5-12 years old participated in the study. Hepatic fat was assessed by magnetic resonance imaging. Fasting blood biochemical parameters were measured and HOMA-IR calculated. Peripheral blood mononuclear cells (PBMC)-derived miRNA profiles associated with MAFLD (≥5.5% hepatic fat) and IR (HOMA-IR ≥2.5) were identified using untargeted high-throughput miRNAs sequencing (RNA-seq).

RESULTS

A total of 2123 PBMC-derived miRNAs were identified in children with (21.4%) or without MAFLD. Among them, hsa-miR-143-3p, hsa-miR-142-5p and hsa-miR-660-5p were up-regulated, and p-hsa-miR-247, hsa-let-7a-5p and hsa-miR-6823-3p down-regulated. Importantly, children with MAFLD had consistently higher miR-660-5p expression levels than their peers without it (p < 0.01), regardless of weight status. A total of 2124 PBMC-derived miRNA were identified in children with IR (28.6%) versus children without IR, where thirteen of them were dysregulated (p < 0.05) in children with IR. In addition, children with IR showed higher levels of miR-374a-5p and miR-190a-5p (p < 0.01) and lower levels of miR-4284 and miR-4791 (p < 005), than their peers without IR in both the whole sample and in those with overweight or obesity.

CONCLUSIONS

Our study results suggest circulating miR-660-5p as a potential biomarker of the presence of MAFLD in preadolescent children while circulating miR-320a, miR-142-3p, miR-190a-5p, miR-374a-5p and let-7 family miRNAs could serve as potential biomarkers of IR in children.

Metabolic syndrome screening in adolescents: New scores AI_METS based on artificial intelligence techniques

BACKGROUND AND AIMS

Metabolic syndrome (MetS) definitions in adolescents based on the percentiles of its components are rather complicated to use in clinical practice. The aim of this study was to test the validity of artificial intelligence (AI)-based scores (AI_METS) that do not use these percentiles for MetS screening for adolescents.

METHODS AND RESULTS

This study included 1086 adolescents aged 12 to 18. The cohort underwent anthropometric measurements and blood tests. Mean blood pressure (MBP), and triglyceride glucose index (TyG) were calculated. Explainable AI methods are used to extract the learned function. Gini importance techniques were tested and used to build new scores for the screening of MetS. IDF, Cook, De Ferranti, Viner, and Weiss definitions of MetS were used to test the validity of these scores. MetS prevalence was 0.4%-4.7% according to these definitions. AI_METS used age, waist circumference, MBP, and TyG index. They offer area under the curves (AUCs) 0.91, 0.93, 0.89, 0.93, and 0.98; specificity 81%, 75%, 72%, 80%, and 97%; and sensitivity 90%, 100%, 90%, 100%, and 100%, respectively, for the detection of MetS according to these definitions. Considering only MBP offers a better specificity and sensitivity to detect MetS than considering only TyG index. MBP offers slightly lower performance than AI_METS.

CONCLUSION

AI techniques have proven their ability to extract knowledge from data. They allowed us to generate new scores for MetS detection in adolescents without using specific percentiles for each component. Although these scores are less intuitive than the percentile-based definition, their accuracy is rather effective for the detection of MetS.

Physical Fitness, Screen Time and Sleep Habits According to Obesity Levels in Schoolchildren: Findings from the Health Survey of the Extreme South of Chile

Obesity is a worry because it is associated with a greater burden of disease, and it has been shown to be related to the health habits and physical condition of children and adolescents.

OBJECTIVE

To associate physical fitness, screen time, and sleep habits with the different categories of obesity in schoolchildren from the extreme south of Chile.

METHODS

583 schoolchildren were included in this cross-sectional analysis. The screen time and sleep habits were measured with the Sleep Self-Report questionnaire, while the physical fitness was assessed with the Alpha Fitness test battery. The Body Mass Index/age (BMI/age) and the Waist-to-Height ratio (WtHr) were used to define adiposity using the following categories: healthy weight/low-risk waist-to-height ratio (H/LR), healthy weight/high-risk waist-to-height ratio (H/HR), overweight/low-risk waist to height ratio (O/LR), and overweight/high-risk waist to height ratio (O/HR).

RESULTS

A considerable number of schoolchildren (23.2%) presented sleep problems, while the mean screen time was 9.3 (95% CI: 8.4; 10.1) hours/day. Schoolchildren classified as H/HR showed better physical fitness than the O/HR group but worse physical fitness than the H/LR group.

CONCLUSIONS

Significant differences were evidenced in the physical fitness between the adiposity categories, which could open future lines of research concerning the characterization of the healthy weight-obese adiposity categories in children.

Diagnostic test accuracy of waist-to-height ratio as a screening tool for cardiovascular risk in children and adolescents: a meta-analysis

CONTEXT

Waist-to-height ratio (WHtR) is a controversial evaluation index of cardiovascular risk factors (CVRFs) in children and adolescents.

OBJECTIVE

To assess the accuracy of WHtR as a measure to screen for clusters of at least one CVRF (CVRF₁), two CVRFs (CVRF₂), and three CVRFs (CVRF₃) in different ages, sexes, regions and cut-offs.

METHODS

The PubMed, Web of Science, EBSCOhost, Springer, Taylor & Francis Online, Wiley Online Library, Wanfang, and CNKI databases were searched for eligible publications up to June 2021. The QUADAS-2 checklist was used to assess the methodology of the included studies.

RESULTS

Twenty-two studies that evaluated 85281 children and adolescents aged 5-19 years were included in the meta-analysis. The AUSROC values were 0.56 (95% CI: 0.54-0.57), 0.82 (95% CI: 0.81-0.83), and 0.89 (95% CI: 0.89-0.90) for CVRF₁, CVRF₂, and CVRF₃, respectively. Higher AUSROC values were found for adolescents (12-19 years), that is, 0.91 (95% CI: 0.88-0.93), 0.90 (95% CI: 0.87-0.92) for males, and 0.91 (95% CI: 0.90-0.91) for a cut-off of ≥ 0.51 in the identification of CVRF₃.

CONCLUSION

WHtR can be used as an accurate screening tool for CVRF₃ and CVRF₂ in children and adolescents, and it is recommended to select different cut-offs according to different ages, sexes, and regions.

Development of a prediction protocol for the screening of metabolic associated fatty liver disease in children with overweight or obesity

BACKGROUND

The early detection and management of children with metabolic associated fatty liver disease (MAFLD) is challenging.

OBJECTIVE

To develop a non-invasive and accurate prediction protocol for the identification of MAFLD among children with overweight/obesity candidates to confirmatory diagnosis.

METHODS

A total of 115 children aged 8-12 years with overweight/obesity, recruited at a primary care, were enrolled in this cross-sectional study. The external validation was performed using a cohort of children with overweight/obesity (N = 46) aged 8.5-14.0 years. MAFLD (≥5.5% hepatic fat) was diagnosed by magnetic resonance imaging (MRI). Fasting blood biochemical parameters were measured, and 25 candidates' single nucleotide polymorphisms (SNPs) were determined. Variables potentially associated with the presence of MAFLD were included in a multivariate logistic regression.

RESULTS

Children with MAFLD (36%) showed higher plasma triglycerides (TG), insulin, homeostasis model assessment of insulin resistance (HOMA-IR), alanine aminotransferase (ALT), aspartate transaminase (AST), glutamyl-transferase (GGT) and ferritin (p < 0.05). The distribution of the risk-alleles of PPARGrs13081389, PPARGrs1801282, HFErs1800562 and PNLPLA3rs4823173 was significantly different between children with and without MAFLD (p < 0.05). Three biochemical- and/or SNPs-based predictive models were developed, showing strong discriminatory capacity (AUC-ROC: 0.708-0.888) but limited diagnostic performance (sensitivity 67%-82% and specificity 63%-69%). A prediction protocol with elevated sensitivity (72%) and specificity (84%) based on two consecutive steps was developed. The external validation showed similar results: sensitivity of 70% and specificity of 85%.

CONCLUSIONS

The HEPAKID prediction protocol is an accurate, easy to implant, minimally invasive and low economic cost tool useful for the early identification and management of paediatric MAFLD in primary care.

Effectiveness of a body shape index in predicting pediatric high blood pressure

BACKGROUND

A body shape index (ABSI) is an emerging anthropometric indicator, challenging two traditional parameters: body mass index (BMI) and waist circumference (WC). We aimed to systematically compare and validate the capability of anthropometric indicators for determining pediatric high blood pressure (HBP).

METHODS

A total of 3150 participants aged 7-17 years were enrolled from Suzhou, China. Areas under the receiver operating characteristic curve (AUC) were obtained to evaluate the performance of anthropometric indicators in detecting HBP. DeLong's test was used to examine whether the AUCs of anthropometric indicators in contrast to BMI or original ABSI were statistically different. Furthermore, a meta-analysis was performed to combine results from this study and five similar articles from databases.

RESULTS

In Suzhou population, BMI exhibited the largest AUC (AUC = 0.705), followed by WC (AUC = 0.669) and original ABSI (AUC = 0.514). Modified ABSI (AUC: 0.537-0.681), although had slightly better performance than original ABSI, was still less valuable than BMI (P &lt; 0.05), either in the total sample or in boys. The meta-analysis with 21108 children and adolescents subsequently confirms the results derived from Suzhou population.

CONCLUSIONS

In predicting pediatric HBP, original ABSI and modified ABSI underperform BMI and WC.

IMPACT

The current study is the first to evaluate whether original ABSI or modified ABSI is comparable to BMI and WC for screening HBP in children and adolescents. In predicting pediatric HBP, original ABSI and modified ABSI do not perform as well as traditional anthropometric indicators, such as BMI and WC. BMI remains the optimal indicator in pediatric HBP screening. This study provides a theoretical basis for the early identification of HBP in children and adolescents by adopting effective predictors.

Plasma exosomal IRAK1 can be a potential biomarker for predicting the treatment response to renin-angiotensin system inhibitors in patients with IgA nephropathy

Background

Renin-angiotensin system inhibitors (RASi) are the first choice and basic therapy for the treatment of IgA nephropathy (IgAN) with proteinuria. However, approximately 40% of patients have no response to RASi treatment. The aim of this study was to screen potential biomarkers for predicting the treatment response of RASi in patients with IgAN.

Methods

We included IgAN patients who were treatment-naive. They received supportive treatment, including a maximum tolerant dose of RASi for 3 months. According to the degree of decrease in proteinuria after 3 months of follow-up, these patients were divided into a sensitive group and a resistant group. The plasma of the two groups of patients was collected, and the exosomes were extracted for high-throughput sequencing. The screening of hub genes was performed using a weighted gene co-expression network (WGCNA) and filtering differentially expressed genes (DEGs). We randomly selected 20 patients in the sensitive group and 20 patients in the resistant group for hub gene validation by real-time quantitative polymerase chain reaction (qRT−PCR). A receiver operating characteristic (ROC) curve was used to evaluate hub genes that predicted the efficacy of the RASi response among the 40 validation patients.

Results

After screening 370 IgAN patients according to the inclusion and exclusion criteria and the RASi treatment response evaluation, there were 38 patients in the sensitive group and 32 patients in the resistant group. IRAK1, ABCD1 and PLXNB3 were identified as hub genes by analyzing the high-throughput sequencing of the plasma exosomes of the two groups through WGCNA and DEGs screening. The sequencing data were consistent with the validation data showing that these three hub genes were upregulated in the resistant group compared with the sensitive group. The ROC curve indicated that IRAK1 was a good biomarker to predict the therapeutic response of RASi in patients with IgAN.

Conclusions

Plasma exosomal IRAK1 can be a potential biomarker for predicting the treatment response of RASi in patients with IgAN.

Association between dietary acid load and metabolic health status in overweight and obese adolescents

The relationship between dietary acid load (DAL) and metabolic health status in adolescents has not been studied yet. We aimed to examine the association between DAL and metabolic health status in Iranian overweight/obese adolescents. This cross-sectional study included 203 overweight/obese adolescents selected by a multistage cluster random sampling method. Dietary intakes were assessed using a validated 147-item food frequency questionnaire (FFQ). Anthropometric indices and blood pressure values were measured. Fasting blood samples were obtained to determine glucose, insulin, and lipid profiles. Based on two methods (International Diabetes Federation (IDF) criteria and combination of IDF with Homeostasis Model Assessment Insulin Resistance (HOMA-IR)), participants were classified into metabolically healthy obese (MHO) or unhealthy obese (MUO). Adolescents in the highest tertile of potential renal acid load (PRAL) and net endogenous acid production (NEAP), compared with those in the lowest tertile, had 172% (95% CI 1.32–5.59) and 161% (95% CI 1.26–5.41) higher odds of MUO status, based on IDF criteria. This association was significant after adjustment for age, sex, and energy intake (PRAL: OR 2.42; 95% CI CI 1.13–5.15; NEAP: OR 2.52; 95% CI 1.17–5.41); but it disappeared after adjustment for other confounders. Based on IDF/HOMA-IR definition, there was a significant positive association between PRAL and being MUO only in the crude model (OR 2.37; 95% CI 1.13–4.96). The stratified analysis revealed that these associations for NEAP scores were stronger among overweight subjects than obese individuals, based on both metabolic status definitions. However, after adjustment for all potential confounders these relations were insignificant. Having higher DAL might be associated with higher odds of MUO phenotype in Iranian overweight/obese adolescents. More prospective studies are warranted to confirm this finding.

Evaluation of Circulating Chitotriosidase Activity in Children with Obesity

Childhood obesity progresses to metabolic disturbances via low-grade inflammation. Identifying novel molecules that reflect the activity of the immune responses is critical in understanding its underlying pathogenesis. Our exploratory study aimed to evaluate the change of chitotriosidase (CHIT1) plasma activity according to Body Mass Index (BMI)-for-age z score in pediatric patients. The study evaluated 68 children consisting of 47.1% girls with a mean age of 12.47 ± 3.71 years and 52.9% boys with a mean age of 11.93 ± 3.18 years. The effect of the most frequent CHIT1 gene variants, the 24 base pair duplication (dup24) and G102S polymorphism, upon the association between circulating CHIT1 activity and the obesity level, was also investigated. A significantly higher logCHIT1 plasma activity was found in children with extreme obesity than in children with overweight (p = 0.048 for the uncorrected CHIT1 and 0.026 for the corrected CHIT1). The BMI-for-age z score significantly (p = 0.031) predicts increased CHIT1 activity in children with overweight, obesity, and extreme obesity after controlling for the two gene variants, age, gender, and time since weight gain. Dup24 and G102S polymorphism were significant independent predictors (p-values < 0.002) for the change of CHIT1 plasma activity. Circulating CHIT1 might be an accurate indicator of inflammation in children with obesity. Its role and the effect of the dup24 and G102S variants on the CHIT1 activity should be validated in a larger cohort.

Determinants of Waist-to-Height Ratio and Its Relation to Hypertension among School Children in India: A Multicenter Study

OBJECTIVE

To study the factors associated with waist-to-height ratio (WHtR) among school children aged 5-15 y and its association with hypertension.

METHODS

In this cross-sectional study, data on background characteristics, socioeconomic status (SES), anthropometric parameters, and blood pressure were obtained from school children from three states of India. WHtR ≥ 0.5 was defined as obesity and hypertensives were defined based on Fourth Report criteria. Descriptive statistics were applied and multiple linear regression was done to identify factors associated with WHtR. A receiver operating characteristics (ROC) analysis was used to evaluate the predictive ability of WHtR to predict hypertension RESULTS: The mean WHtR among the 12,068 students was 0.40 (± 0.05) and it showed a U-shaped distribution with age with trough at 10 y of age for both genders. Mean WHtR was higher among residents of Manipur, among boys and hypertensives. WHtR was positively associated with weight > 30 kg, male gender, schools with high SES, Manipur and Goa region, and negatively associated with age > 10 y. The area under the ROC curve of WHtR for diagnosis of hypertension was low 0.544 (95% CI 0.532, 0.556).

CONCLUSION

There is a nonlinear relation between age, gender, and WHtR, which varies by geographical region and HT. This would need to be kept in mind while using it to identify obesity in children, though its discriminant value for hypertension is low.

Adiposity measures in screening for metabolic syndrome among Chinese children and adolescents

BACKGROUND

Existing various and complicated metabolic syndrome (MetS) definitions have contributed to the difficulty in assessing MetS in children and adolescents, and therefore it is urgently needed to develop a convenient and effective screening tool for pediatric MetS. This study aimed to identify the optimal adiposity measure to screen for pediatric MetS.

METHODS

The cross-sectional data was collected from 8,150 children and adolescents aged 7-17 y living in southern China. Anthropometric indices, blood lipids, and serum glucose were determined. Results of two commonly used MetS definitions were compared: International Diabetes Federation (IDF) and National Cholesterol Education Program Adult Treatment Panel Ⅲ (NCEP-ATP) modified by Cook. Receiver operating characteristic curve analyses were performed and areas under the curve (AUCs) were calculated to determine the optimal index for MetS screening.

RESULTS

MetS prevalence assessed by NCEP-ATP was significantly higher than that by IDF (6.2% vs. 1.5%, p<0.001). Waist-to-height ratio (WHtR) showed the highest screening power for MetS defined by both IDF and NCEP-ATP (AUC 0.932 and 0.900, respectively), and its optimal cut-off point was 0.48 by both IDF and NCEP-ATP definition (sensitivity 0.944 and 0.847, specificity 0.800 and 0.830, respectively), regardless of age or sex. When taking sex diversity into account, the optimal WHtR cut-off point was 0.49 (IDF) or 0.50 (NCEP-ATP) in boys, and 0.46 (both definitions) in girls.

CONCLUSIONS

Among children and adolescents aged 7-17 y in southern China, a WHtR greater than 0.48 can be a simple but effective screening tool for MetS.